These files are a subset of the python-2.7.2.tgz distribution from python.org. Changed files from PyMod-2.7.2 have been copied into the corresponding directories of this tree, replacing the original files in the distribution. Signed-off-by: daryl.mcdaniel@intel.com git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13197 6f19259b-4bc3-4df7-8a09-765794883524
		
			
				
	
	
		
			764 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			764 lines
		
	
	
		
			24 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| """A flow graph representation for Python bytecode"""
 | |
| 
 | |
| import dis
 | |
| import types
 | |
| import sys
 | |
| 
 | |
| from compiler import misc
 | |
| from compiler.consts \
 | |
|      import CO_OPTIMIZED, CO_NEWLOCALS, CO_VARARGS, CO_VARKEYWORDS
 | |
| 
 | |
| class FlowGraph:
 | |
|     def __init__(self):
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|         self.current = self.entry = Block()
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|         self.exit = Block("exit")
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|         self.blocks = misc.Set()
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|         self.blocks.add(self.entry)
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|         self.blocks.add(self.exit)
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| 
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|     def startBlock(self, block):
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|         if self._debug:
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|             if self.current:
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|                 print "end", repr(self.current)
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|                 print "    next", self.current.next
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|                 print "    prev", self.current.prev
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|                 print "   ", self.current.get_children()
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|             print repr(block)
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|         self.current = block
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| 
 | |
|     def nextBlock(self, block=None):
 | |
|         # XXX think we need to specify when there is implicit transfer
 | |
|         # from one block to the next.  might be better to represent this
 | |
|         # with explicit JUMP_ABSOLUTE instructions that are optimized
 | |
|         # out when they are unnecessary.
 | |
|         #
 | |
|         # I think this strategy works: each block has a child
 | |
|         # designated as "next" which is returned as the last of the
 | |
|         # children.  because the nodes in a graph are emitted in
 | |
|         # reverse post order, the "next" block will always be emitted
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|         # immediately after its parent.
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|         # Worry: maintaining this invariant could be tricky
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|         if block is None:
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|             block = self.newBlock()
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| 
 | |
|         # Note: If the current block ends with an unconditional control
 | |
|         # transfer, then it is techically incorrect to add an implicit
 | |
|         # transfer to the block graph. Doing so results in code generation
 | |
|         # for unreachable blocks.  That doesn't appear to be very common
 | |
|         # with Python code and since the built-in compiler doesn't optimize
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|         # it out we don't either.
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|         self.current.addNext(block)
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|         self.startBlock(block)
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| 
 | |
|     def newBlock(self):
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|         b = Block()
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|         self.blocks.add(b)
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|         return b
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| 
 | |
|     def startExitBlock(self):
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|         self.startBlock(self.exit)
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| 
 | |
|     _debug = 0
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| 
 | |
|     def _enable_debug(self):
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|         self._debug = 1
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| 
 | |
|     def _disable_debug(self):
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|         self._debug = 0
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| 
 | |
|     def emit(self, *inst):
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|         if self._debug:
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|             print "\t", inst
 | |
|         if len(inst) == 2 and isinstance(inst[1], Block):
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|             self.current.addOutEdge(inst[1])
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|         self.current.emit(inst)
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| 
 | |
|     def getBlocksInOrder(self):
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|         """Return the blocks in reverse postorder
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| 
 | |
|         i.e. each node appears before all of its successors
 | |
|         """
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|         order = order_blocks(self.entry, self.exit)
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|         return order
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| 
 | |
|     def getBlocks(self):
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|         return self.blocks.elements()
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| 
 | |
|     def getRoot(self):
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|         """Return nodes appropriate for use with dominator"""
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|         return self.entry
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| 
 | |
|     def getContainedGraphs(self):
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|         l = []
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|         for b in self.getBlocks():
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|             l.extend(b.getContainedGraphs())
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|         return l
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| 
 | |
| 
 | |
| def order_blocks(start_block, exit_block):
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|     """Order blocks so that they are emitted in the right order"""
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|     # Rules:
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|     # - when a block has a next block, the next block must be emitted just after
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|     # - when a block has followers (relative jumps), it must be emitted before
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|     #   them
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|     # - all reachable blocks must be emitted
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|     order = []
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| 
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|     # Find all the blocks to be emitted.
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|     remaining = set()
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|     todo = [start_block]
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|     while todo:
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|         b = todo.pop()
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|         if b in remaining:
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|             continue
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|         remaining.add(b)
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|         for c in b.get_children():
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|             if c not in remaining:
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|                 todo.append(c)
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| 
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|     # A block is dominated by another block if that block must be emitted
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|     # before it.
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|     dominators = {}
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|     for b in remaining:
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|         if __debug__ and b.next:
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|             assert b is b.next[0].prev[0], (b, b.next)
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|         # Make sure every block appears in dominators, even if no
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|         # other block must precede it.
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|         dominators.setdefault(b, set())
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|         # preceeding blocks dominate following blocks
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|         for c in b.get_followers():
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|             while 1:
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|                 dominators.setdefault(c, set()).add(b)
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|                 # Any block that has a next pointer leading to c is also
 | |
|                 # dominated because the whole chain will be emitted at once.
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|                 # Walk backwards and add them all.
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|                 if c.prev and c.prev[0] is not b:
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|                     c = c.prev[0]
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|                 else:
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|                     break
 | |
| 
 | |
|     def find_next():
 | |
|         # Find a block that can be emitted next.
 | |
|         for b in remaining:
 | |
|             for c in dominators[b]:
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|                 if c in remaining:
 | |
|                     break # can't emit yet, dominated by a remaining block
 | |
|             else:
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|                 return b
 | |
|         assert 0, 'circular dependency, cannot find next block'
 | |
| 
 | |
|     b = start_block
 | |
|     while 1:
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|         order.append(b)
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|         remaining.discard(b)
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|         if b.next:
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|             b = b.next[0]
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|             continue
 | |
|         elif b is not exit_block and not b.has_unconditional_transfer():
 | |
|             order.append(exit_block)
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|         if not remaining:
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|             break
 | |
|         b = find_next()
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|     return order
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| 
 | |
| 
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| class Block:
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|     _count = 0
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| 
 | |
|     def __init__(self, label=''):
 | |
|         self.insts = []
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|         self.outEdges = set()
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|         self.label = label
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|         self.bid = Block._count
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|         self.next = []
 | |
|         self.prev = []
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|         Block._count = Block._count + 1
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| 
 | |
|     def __repr__(self):
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|         if self.label:
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|             return "<block %s id=%d>" % (self.label, self.bid)
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|         else:
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|             return "<block id=%d>" % (self.bid)
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| 
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|     def __str__(self):
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|         insts = map(str, self.insts)
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|         return "<block %s %d:\n%s>" % (self.label, self.bid,
 | |
|                                        '\n'.join(insts))
 | |
| 
 | |
|     def emit(self, inst):
 | |
|         op = inst[0]
 | |
|         self.insts.append(inst)
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| 
 | |
|     def getInstructions(self):
 | |
|         return self.insts
 | |
| 
 | |
|     def addOutEdge(self, block):
 | |
|         self.outEdges.add(block)
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| 
 | |
|     def addNext(self, block):
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|         self.next.append(block)
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|         assert len(self.next) == 1, map(str, self.next)
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|         block.prev.append(self)
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|         assert len(block.prev) == 1, map(str, block.prev)
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| 
 | |
|     _uncond_transfer = ('RETURN_VALUE', 'RAISE_VARARGS',
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|                         'JUMP_ABSOLUTE', 'JUMP_FORWARD', 'CONTINUE_LOOP',
 | |
|                         )
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| 
 | |
|     def has_unconditional_transfer(self):
 | |
|         """Returns True if there is an unconditional transfer to an other block
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|         at the end of this block. This means there is no risk for the bytecode
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|         executer to go past this block's bytecode."""
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|         try:
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|             op, arg = self.insts[-1]
 | |
|         except (IndexError, ValueError):
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|             return
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|         return op in self._uncond_transfer
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| 
 | |
|     def get_children(self):
 | |
|         return list(self.outEdges) + self.next
 | |
| 
 | |
|     def get_followers(self):
 | |
|         """Get the whole list of followers, including the next block."""
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|         followers = set(self.next)
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|         # Blocks that must be emitted *after* this one, because of
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|         # bytecode offsets (e.g. relative jumps) pointing to them.
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|         for inst in self.insts:
 | |
|             if inst[0] in PyFlowGraph.hasjrel:
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|                 followers.add(inst[1])
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|         return followers
 | |
| 
 | |
|     def getContainedGraphs(self):
 | |
|         """Return all graphs contained within this block.
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| 
 | |
|         For example, a MAKE_FUNCTION block will contain a reference to
 | |
|         the graph for the function body.
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|         """
 | |
|         contained = []
 | |
|         for inst in self.insts:
 | |
|             if len(inst) == 1:
 | |
|                 continue
 | |
|             op = inst[1]
 | |
|             if hasattr(op, 'graph'):
 | |
|                 contained.append(op.graph)
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|         return contained
 | |
| 
 | |
| # flags for code objects
 | |
| 
 | |
| # the FlowGraph is transformed in place; it exists in one of these states
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| RAW = "RAW"
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| FLAT = "FLAT"
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| CONV = "CONV"
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| DONE = "DONE"
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| 
 | |
| class PyFlowGraph(FlowGraph):
 | |
|     super_init = FlowGraph.__init__
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| 
 | |
|     def __init__(self, name, filename, args=(), optimized=0, klass=None):
 | |
|         self.super_init()
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|         self.name = name
 | |
|         self.filename = filename
 | |
|         self.docstring = None
 | |
|         self.args = args # XXX
 | |
|         self.argcount = getArgCount(args)
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|         self.klass = klass
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|         if optimized:
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|             self.flags = CO_OPTIMIZED | CO_NEWLOCALS
 | |
|         else:
 | |
|             self.flags = 0
 | |
|         self.consts = []
 | |
|         self.names = []
 | |
|         # Free variables found by the symbol table scan, including
 | |
|         # variables used only in nested scopes, are included here.
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|         self.freevars = []
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|         self.cellvars = []
 | |
|         # The closure list is used to track the order of cell
 | |
|         # variables and free variables in the resulting code object.
 | |
|         # The offsets used by LOAD_CLOSURE/LOAD_DEREF refer to both
 | |
|         # kinds of variables.
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|         self.closure = []
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|         self.varnames = list(args) or []
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|         for i in range(len(self.varnames)):
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|             var = self.varnames[i]
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|             if isinstance(var, TupleArg):
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|                 self.varnames[i] = var.getName()
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|         self.stage = RAW
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| 
 | |
|     def setDocstring(self, doc):
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|         self.docstring = doc
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| 
 | |
|     def setFlag(self, flag):
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|         self.flags = self.flags | flag
 | |
|         if flag == CO_VARARGS:
 | |
|             self.argcount = self.argcount - 1
 | |
| 
 | |
|     def checkFlag(self, flag):
 | |
|         if self.flags & flag:
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|             return 1
 | |
| 
 | |
|     def setFreeVars(self, names):
 | |
|         self.freevars = list(names)
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| 
 | |
|     def setCellVars(self, names):
 | |
|         self.cellvars = names
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| 
 | |
|     def getCode(self):
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|         """Get a Python code object"""
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|         assert self.stage == RAW
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|         self.computeStackDepth()
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|         self.flattenGraph()
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|         assert self.stage == FLAT
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|         self.convertArgs()
 | |
|         assert self.stage == CONV
 | |
|         self.makeByteCode()
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|         assert self.stage == DONE
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|         return self.newCodeObject()
 | |
| 
 | |
|     def dump(self, io=None):
 | |
|         if io:
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|             save = sys.stdout
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|             sys.stdout = io
 | |
|         pc = 0
 | |
|         for t in self.insts:
 | |
|             opname = t[0]
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|             if opname == "SET_LINENO":
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|                 print
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|             if len(t) == 1:
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|                 print "\t", "%3d" % pc, opname
 | |
|                 pc = pc + 1
 | |
|             else:
 | |
|                 print "\t", "%3d" % pc, opname, t[1]
 | |
|                 pc = pc + 3
 | |
|         if io:
 | |
|             sys.stdout = save
 | |
| 
 | |
|     def computeStackDepth(self):
 | |
|         """Compute the max stack depth.
 | |
| 
 | |
|         Approach is to compute the stack effect of each basic block.
 | |
|         Then find the path through the code with the largest total
 | |
|         effect.
 | |
|         """
 | |
|         depth = {}
 | |
|         exit = None
 | |
|         for b in self.getBlocks():
 | |
|             depth[b] = findDepth(b.getInstructions())
 | |
| 
 | |
|         seen = {}
 | |
| 
 | |
|         def max_depth(b, d):
 | |
|             if b in seen:
 | |
|                 return d
 | |
|             seen[b] = 1
 | |
|             d = d + depth[b]
 | |
|             children = b.get_children()
 | |
|             if children:
 | |
|                 return max([max_depth(c, d) for c in children])
 | |
|             else:
 | |
|                 if not b.label == "exit":
 | |
|                     return max_depth(self.exit, d)
 | |
|                 else:
 | |
|                     return d
 | |
| 
 | |
|         self.stacksize = max_depth(self.entry, 0)
 | |
| 
 | |
|     def flattenGraph(self):
 | |
|         """Arrange the blocks in order and resolve jumps"""
 | |
|         assert self.stage == RAW
 | |
|         self.insts = insts = []
 | |
|         pc = 0
 | |
|         begin = {}
 | |
|         end = {}
 | |
|         for b in self.getBlocksInOrder():
 | |
|             begin[b] = pc
 | |
|             for inst in b.getInstructions():
 | |
|                 insts.append(inst)
 | |
|                 if len(inst) == 1:
 | |
|                     pc = pc + 1
 | |
|                 elif inst[0] != "SET_LINENO":
 | |
|                     # arg takes 2 bytes
 | |
|                     pc = pc + 3
 | |
|             end[b] = pc
 | |
|         pc = 0
 | |
|         for i in range(len(insts)):
 | |
|             inst = insts[i]
 | |
|             if len(inst) == 1:
 | |
|                 pc = pc + 1
 | |
|             elif inst[0] != "SET_LINENO":
 | |
|                 pc = pc + 3
 | |
|             opname = inst[0]
 | |
|             if opname in self.hasjrel:
 | |
|                 oparg = inst[1]
 | |
|                 offset = begin[oparg] - pc
 | |
|                 insts[i] = opname, offset
 | |
|             elif opname in self.hasjabs:
 | |
|                 insts[i] = opname, begin[inst[1]]
 | |
|         self.stage = FLAT
 | |
| 
 | |
|     hasjrel = set()
 | |
|     for i in dis.hasjrel:
 | |
|         hasjrel.add(dis.opname[i])
 | |
|     hasjabs = set()
 | |
|     for i in dis.hasjabs:
 | |
|         hasjabs.add(dis.opname[i])
 | |
| 
 | |
|     def convertArgs(self):
 | |
|         """Convert arguments from symbolic to concrete form"""
 | |
|         assert self.stage == FLAT
 | |
|         self.consts.insert(0, self.docstring)
 | |
|         self.sort_cellvars()
 | |
|         for i in range(len(self.insts)):
 | |
|             t = self.insts[i]
 | |
|             if len(t) == 2:
 | |
|                 opname, oparg = t
 | |
|                 conv = self._converters.get(opname, None)
 | |
|                 if conv:
 | |
|                     self.insts[i] = opname, conv(self, oparg)
 | |
|         self.stage = CONV
 | |
| 
 | |
|     def sort_cellvars(self):
 | |
|         """Sort cellvars in the order of varnames and prune from freevars.
 | |
|         """
 | |
|         cells = {}
 | |
|         for name in self.cellvars:
 | |
|             cells[name] = 1
 | |
|         self.cellvars = [name for name in self.varnames
 | |
|                          if name in cells]
 | |
|         for name in self.cellvars:
 | |
|             del cells[name]
 | |
|         self.cellvars = self.cellvars + cells.keys()
 | |
|         self.closure = self.cellvars + self.freevars
 | |
| 
 | |
|     def _lookupName(self, name, list):
 | |
|         """Return index of name in list, appending if necessary
 | |
| 
 | |
|         This routine uses a list instead of a dictionary, because a
 | |
|         dictionary can't store two different keys if the keys have the
 | |
|         same value but different types, e.g. 2 and 2L.  The compiler
 | |
|         must treat these two separately, so it does an explicit type
 | |
|         comparison before comparing the values.
 | |
|         """
 | |
|         t = type(name)
 | |
|         for i in range(len(list)):
 | |
|             if t == type(list[i]) and list[i] == name:
 | |
|                 return i
 | |
|         end = len(list)
 | |
|         list.append(name)
 | |
|         return end
 | |
| 
 | |
|     _converters = {}
 | |
|     def _convert_LOAD_CONST(self, arg):
 | |
|         if hasattr(arg, 'getCode'):
 | |
|             arg = arg.getCode()
 | |
|         return self._lookupName(arg, self.consts)
 | |
| 
 | |
|     def _convert_LOAD_FAST(self, arg):
 | |
|         self._lookupName(arg, self.names)
 | |
|         return self._lookupName(arg, self.varnames)
 | |
|     _convert_STORE_FAST = _convert_LOAD_FAST
 | |
|     _convert_DELETE_FAST = _convert_LOAD_FAST
 | |
| 
 | |
|     def _convert_LOAD_NAME(self, arg):
 | |
|         if self.klass is None:
 | |
|             self._lookupName(arg, self.varnames)
 | |
|         return self._lookupName(arg, self.names)
 | |
| 
 | |
|     def _convert_NAME(self, arg):
 | |
|         if self.klass is None:
 | |
|             self._lookupName(arg, self.varnames)
 | |
|         return self._lookupName(arg, self.names)
 | |
|     _convert_STORE_NAME = _convert_NAME
 | |
|     _convert_DELETE_NAME = _convert_NAME
 | |
|     _convert_IMPORT_NAME = _convert_NAME
 | |
|     _convert_IMPORT_FROM = _convert_NAME
 | |
|     _convert_STORE_ATTR = _convert_NAME
 | |
|     _convert_LOAD_ATTR = _convert_NAME
 | |
|     _convert_DELETE_ATTR = _convert_NAME
 | |
|     _convert_LOAD_GLOBAL = _convert_NAME
 | |
|     _convert_STORE_GLOBAL = _convert_NAME
 | |
|     _convert_DELETE_GLOBAL = _convert_NAME
 | |
| 
 | |
|     def _convert_DEREF(self, arg):
 | |
|         self._lookupName(arg, self.names)
 | |
|         self._lookupName(arg, self.varnames)
 | |
|         return self._lookupName(arg, self.closure)
 | |
|     _convert_LOAD_DEREF = _convert_DEREF
 | |
|     _convert_STORE_DEREF = _convert_DEREF
 | |
| 
 | |
|     def _convert_LOAD_CLOSURE(self, arg):
 | |
|         self._lookupName(arg, self.varnames)
 | |
|         return self._lookupName(arg, self.closure)
 | |
| 
 | |
|     _cmp = list(dis.cmp_op)
 | |
|     def _convert_COMPARE_OP(self, arg):
 | |
|         return self._cmp.index(arg)
 | |
| 
 | |
|     # similarly for other opcodes...
 | |
| 
 | |
|     for name, obj in locals().items():
 | |
|         if name[:9] == "_convert_":
 | |
|             opname = name[9:]
 | |
|             _converters[opname] = obj
 | |
|     del name, obj, opname
 | |
| 
 | |
|     def makeByteCode(self):
 | |
|         assert self.stage == CONV
 | |
|         self.lnotab = lnotab = LineAddrTable()
 | |
|         for t in self.insts:
 | |
|             opname = t[0]
 | |
|             if len(t) == 1:
 | |
|                 lnotab.addCode(self.opnum[opname])
 | |
|             else:
 | |
|                 oparg = t[1]
 | |
|                 if opname == "SET_LINENO":
 | |
|                     lnotab.nextLine(oparg)
 | |
|                     continue
 | |
|                 hi, lo = twobyte(oparg)
 | |
|                 try:
 | |
|                     lnotab.addCode(self.opnum[opname], lo, hi)
 | |
|                 except ValueError:
 | |
|                     print opname, oparg
 | |
|                     print self.opnum[opname], lo, hi
 | |
|                     raise
 | |
|         self.stage = DONE
 | |
| 
 | |
|     opnum = {}
 | |
|     for num in range(len(dis.opname)):
 | |
|         opnum[dis.opname[num]] = num
 | |
|     del num
 | |
| 
 | |
|     def newCodeObject(self):
 | |
|         assert self.stage == DONE
 | |
|         if (self.flags & CO_NEWLOCALS) == 0:
 | |
|             nlocals = 0
 | |
|         else:
 | |
|             nlocals = len(self.varnames)
 | |
|         argcount = self.argcount
 | |
|         if self.flags & CO_VARKEYWORDS:
 | |
|             argcount = argcount - 1
 | |
|         return types.CodeType(argcount, nlocals, self.stacksize, self.flags,
 | |
|                         self.lnotab.getCode(), self.getConsts(),
 | |
|                         tuple(self.names), tuple(self.varnames),
 | |
|                         self.filename, self.name, self.lnotab.firstline,
 | |
|                         self.lnotab.getTable(), tuple(self.freevars),
 | |
|                         tuple(self.cellvars))
 | |
| 
 | |
|     def getConsts(self):
 | |
|         """Return a tuple for the const slot of the code object
 | |
| 
 | |
|         Must convert references to code (MAKE_FUNCTION) to code
 | |
|         objects recursively.
 | |
|         """
 | |
|         l = []
 | |
|         for elt in self.consts:
 | |
|             if isinstance(elt, PyFlowGraph):
 | |
|                 elt = elt.getCode()
 | |
|             l.append(elt)
 | |
|         return tuple(l)
 | |
| 
 | |
| def isJump(opname):
 | |
|     if opname[:4] == 'JUMP':
 | |
|         return 1
 | |
| 
 | |
| class TupleArg:
 | |
|     """Helper for marking func defs with nested tuples in arglist"""
 | |
|     def __init__(self, count, names):
 | |
|         self.count = count
 | |
|         self.names = names
 | |
|     def __repr__(self):
 | |
|         return "TupleArg(%s, %s)" % (self.count, self.names)
 | |
|     def getName(self):
 | |
|         return ".%d" % self.count
 | |
| 
 | |
| def getArgCount(args):
 | |
|     argcount = len(args)
 | |
|     if args:
 | |
|         for arg in args:
 | |
|             if isinstance(arg, TupleArg):
 | |
|                 numNames = len(misc.flatten(arg.names))
 | |
|                 argcount = argcount - numNames
 | |
|     return argcount
 | |
| 
 | |
| def twobyte(val):
 | |
|     """Convert an int argument into high and low bytes"""
 | |
|     assert isinstance(val, int)
 | |
|     return divmod(val, 256)
 | |
| 
 | |
| class LineAddrTable:
 | |
|     """lnotab
 | |
| 
 | |
|     This class builds the lnotab, which is documented in compile.c.
 | |
|     Here's a brief recap:
 | |
| 
 | |
|     For each SET_LINENO instruction after the first one, two bytes are
 | |
|     added to lnotab.  (In some cases, multiple two-byte entries are
 | |
|     added.)  The first byte is the distance in bytes between the
 | |
|     instruction for the last SET_LINENO and the current SET_LINENO.
 | |
|     The second byte is offset in line numbers.  If either offset is
 | |
|     greater than 255, multiple two-byte entries are added -- see
 | |
|     compile.c for the delicate details.
 | |
|     """
 | |
| 
 | |
|     def __init__(self):
 | |
|         self.code = []
 | |
|         self.codeOffset = 0
 | |
|         self.firstline = 0
 | |
|         self.lastline = 0
 | |
|         self.lastoff = 0
 | |
|         self.lnotab = []
 | |
| 
 | |
|     def addCode(self, *args):
 | |
|         for arg in args:
 | |
|             self.code.append(chr(arg))
 | |
|         self.codeOffset = self.codeOffset + len(args)
 | |
| 
 | |
|     def nextLine(self, lineno):
 | |
|         if self.firstline == 0:
 | |
|             self.firstline = lineno
 | |
|             self.lastline = lineno
 | |
|         else:
 | |
|             # compute deltas
 | |
|             addr = self.codeOffset - self.lastoff
 | |
|             line = lineno - self.lastline
 | |
|             # Python assumes that lineno always increases with
 | |
|             # increasing bytecode address (lnotab is unsigned char).
 | |
|             # Depending on when SET_LINENO instructions are emitted
 | |
|             # this is not always true.  Consider the code:
 | |
|             #     a = (1,
 | |
|             #          b)
 | |
|             # In the bytecode stream, the assignment to "a" occurs
 | |
|             # after the loading of "b".  This works with the C Python
 | |
|             # compiler because it only generates a SET_LINENO instruction
 | |
|             # for the assignment.
 | |
|             if line >= 0:
 | |
|                 push = self.lnotab.append
 | |
|                 while addr > 255:
 | |
|                     push(255); push(0)
 | |
|                     addr -= 255
 | |
|                 while line > 255:
 | |
|                     push(addr); push(255)
 | |
|                     line -= 255
 | |
|                     addr = 0
 | |
|                 if addr > 0 or line > 0:
 | |
|                     push(addr); push(line)
 | |
|                 self.lastline = lineno
 | |
|                 self.lastoff = self.codeOffset
 | |
| 
 | |
|     def getCode(self):
 | |
|         return ''.join(self.code)
 | |
| 
 | |
|     def getTable(self):
 | |
|         return ''.join(map(chr, self.lnotab))
 | |
| 
 | |
| class StackDepthTracker:
 | |
|     # XXX 1. need to keep track of stack depth on jumps
 | |
|     # XXX 2. at least partly as a result, this code is broken
 | |
| 
 | |
|     def findDepth(self, insts, debug=0):
 | |
|         depth = 0
 | |
|         maxDepth = 0
 | |
|         for i in insts:
 | |
|             opname = i[0]
 | |
|             if debug:
 | |
|                 print i,
 | |
|             delta = self.effect.get(opname, None)
 | |
|             if delta is not None:
 | |
|                 depth = depth + delta
 | |
|             else:
 | |
|                 # now check patterns
 | |
|                 for pat, pat_delta in self.patterns:
 | |
|                     if opname[:len(pat)] == pat:
 | |
|                         delta = pat_delta
 | |
|                         depth = depth + delta
 | |
|                         break
 | |
|                 # if we still haven't found a match
 | |
|                 if delta is None:
 | |
|                     meth = getattr(self, opname, None)
 | |
|                     if meth is not None:
 | |
|                         depth = depth + meth(i[1])
 | |
|             if depth > maxDepth:
 | |
|                 maxDepth = depth
 | |
|             if debug:
 | |
|                 print depth, maxDepth
 | |
|         return maxDepth
 | |
| 
 | |
|     effect = {
 | |
|         'POP_TOP': -1,
 | |
|         'DUP_TOP': 1,
 | |
|         'LIST_APPEND': -1,
 | |
|         'SET_ADD': -1,
 | |
|         'MAP_ADD': -2,
 | |
|         'SLICE+1': -1,
 | |
|         'SLICE+2': -1,
 | |
|         'SLICE+3': -2,
 | |
|         'STORE_SLICE+0': -1,
 | |
|         'STORE_SLICE+1': -2,
 | |
|         'STORE_SLICE+2': -2,
 | |
|         'STORE_SLICE+3': -3,
 | |
|         'DELETE_SLICE+0': -1,
 | |
|         'DELETE_SLICE+1': -2,
 | |
|         'DELETE_SLICE+2': -2,
 | |
|         'DELETE_SLICE+3': -3,
 | |
|         'STORE_SUBSCR': -3,
 | |
|         'DELETE_SUBSCR': -2,
 | |
|         # PRINT_EXPR?
 | |
|         'PRINT_ITEM': -1,
 | |
|         'RETURN_VALUE': -1,
 | |
|         'YIELD_VALUE': -1,
 | |
|         'EXEC_STMT': -3,
 | |
|         'BUILD_CLASS': -2,
 | |
|         'STORE_NAME': -1,
 | |
|         'STORE_ATTR': -2,
 | |
|         'DELETE_ATTR': -1,
 | |
|         'STORE_GLOBAL': -1,
 | |
|         'BUILD_MAP': 1,
 | |
|         'COMPARE_OP': -1,
 | |
|         'STORE_FAST': -1,
 | |
|         'IMPORT_STAR': -1,
 | |
|         'IMPORT_NAME': -1,
 | |
|         'IMPORT_FROM': 1,
 | |
|         'LOAD_ATTR': 0, # unlike other loads
 | |
|         # close enough...
 | |
|         'SETUP_EXCEPT': 3,
 | |
|         'SETUP_FINALLY': 3,
 | |
|         'FOR_ITER': 1,
 | |
|         'WITH_CLEANUP': -1,
 | |
|         }
 | |
|     # use pattern match
 | |
|     patterns = [
 | |
|         ('BINARY_', -1),
 | |
|         ('LOAD_', 1),
 | |
|         ]
 | |
| 
 | |
|     def UNPACK_SEQUENCE(self, count):
 | |
|         return count-1
 | |
|     def BUILD_TUPLE(self, count):
 | |
|         return -count+1
 | |
|     def BUILD_LIST(self, count):
 | |
|         return -count+1
 | |
|     def BUILD_SET(self, count):
 | |
|         return -count+1
 | |
|     def CALL_FUNCTION(self, argc):
 | |
|         hi, lo = divmod(argc, 256)
 | |
|         return -(lo + hi * 2)
 | |
|     def CALL_FUNCTION_VAR(self, argc):
 | |
|         return self.CALL_FUNCTION(argc)-1
 | |
|     def CALL_FUNCTION_KW(self, argc):
 | |
|         return self.CALL_FUNCTION(argc)-1
 | |
|     def CALL_FUNCTION_VAR_KW(self, argc):
 | |
|         return self.CALL_FUNCTION(argc)-2
 | |
|     def MAKE_FUNCTION(self, argc):
 | |
|         return -argc
 | |
|     def MAKE_CLOSURE(self, argc):
 | |
|         # XXX need to account for free variables too!
 | |
|         return -argc
 | |
|     def BUILD_SLICE(self, argc):
 | |
|         if argc == 2:
 | |
|             return -1
 | |
|         elif argc == 3:
 | |
|             return -2
 | |
|     def DUP_TOPX(self, argc):
 | |
|         return argc
 | |
| 
 | |
| findDepth = StackDepthTracker().findDepth
 |